So, recently some fediverse admins (mostly Mastodon) and the founder of Mastodon, Eugen Rochko (Gargron), where contacted by Meta/Facebook for an NDA meeting. We know nothing about it, but we're pretty sure that it was about this project92 thing that Meta/Facebook is creating to "compete" with Twitter.
So a lot of Mastodon admins already singed a pact to immediately block any Meta/Facebook activity in the fediverse as soon as it comes up. My Mastodon instance, fosstodon.org hasn't singed that pact and I'm pretty worried.
The following image is an screenshot of Gargron and dansup (creator of Pixelfed) talking about this. These posts were deleted, even from the wayback machine.
No, that would not be a good reason for me. Generally I would want to discuss everything you could without an NDA. Keep in mind most of the time receiving confidential information is more of a concern then disclosing it. If I then determined I need an NDA, then maybe it is better to have a JDA (Joint Development Agreement) that specifies how jointly developed IP is going to be handled. I am speaking very generally.
In this context maybe the concern would have been business plans not patentable IP for example so maybe they wanted an NDA solely restricted to the business plans of the company and maybe it could be worded very narrowly. Not sure how I would react to that. It would have to be very tightly worded and passed in front of my attorney.
I agree, only crackpots who are afraid of having their unoriginal ideas stolen ask for an NDA for a meeting.
The only thing I can think of is that META is afraid of people finding out how desperately they are trying to stay relevant.
The other reason as someone else pointed out that might be going on at the meeting is a $ amount for a contract of some sort. Companies often want to such business agreements confidential, especially the $ amounts.